Traditional terry socks have sole portions that are composed entirely of terry stitches. The purpose of this structure is, primarily, to warm the feet as well as to function as a shock absorber when walking or running. Because of this structure, the sole portion of the sock tends to be thick across its entire area, preventing the transpiration of sweat and in-shoe humidity, and causing a steamy feel. Moreover, because the sole portion is thick across its entire area, the wearer has to choose a shoe of a larger size than his/her actual foot size. In order to eliminate these characteristic flaws of the traditional terry sock, a sock having terry stitches distributed only over the necessary portions was conceived. This sock, known as a partial terry-stitch sock, is disclosed in Patent Document 1.
[Patent Document 1] Unexamined Utility Model Application Publication No. S60-165405
The sock disclosed in Document 1 has, as described in its claims, “terry stitches distributed in different shapes for the left and right feet in accordance with the shapes of the feet and the shoes. The purpose of this sock is to provide compatibility with the shoe that is worn. The Document does not say anything about varying the thickness of the terry-stitch structure. When walking or running, the heel, sole and toe portions are subjected to different degrees of shock. Ideally each portion has a different terry-stitch thickness and cushion performance. In order to eliminate the flaws in Document 1 above, different terry-stitch lengths may be used for different areas of the terry-stitch structure. A sock having such characteristics is disclosed in Patent Document 2.
[Patent Document 2] Utility Model Publication No. 3037207
The sock disclosed in Document 2 above is, as described in its claim 2, “divided into two or more of the portions including the inserting portion A, the calf portion B, the shin portion C, the heel portion D, the spur portion E, the sole portion F, the instep portion G and the toe portion H with each portion having a different terry length.” For each section, i.e., area unit such as the heel portion and the sole portion, terry stitches of different terry lengths are formed. Within the same section, knitting structures of the same terry lengths are distributed. However, even within the same section, e.g., the sole portion, different areas are of different shapes and are subjected to different degrees of shock when walking or running. The sock disclosed in Document 2 above cannot provide a cushion performance that complies with the ground-touching pressure distribution on the sole portion. Because the terry stitches have the same length within the same section, there is not enough space between the sole of the foot and the sock that eliminate the steamy feel. Patent Document 3 discloses a terry sock that provides increased ventilation.
[Patent Document 3] Unexamined Patent Application Publication No. 2001-295104
The sock disclosed in Document 3, as described in its claim 1, has “an intermediate portion on the back of the sock where terry-stitched portions and plain-stitched portions are mixed.” And as described in its claim 2, “the terry-stitched portions and plain-stitched portions are arranged in a grid.” This structure simply incorporates terry stitches in the midst of plain stitches and does not provide a terry distribution or thickness that comply with the shape and ground-touching pressure of each portion of the sole. Patent Document 4 discloses a product having a variety of terry distributions.
[Patent Document 4] Unexamined Patent Application Publication No. H9-41202
The sock disclosed in Document 4 is, as described in its claim 1, a knit product having a terry-stitch portion characterized by terry loops formed on wales of choice by rotating the knitting cylinder in a reciprocating manner. Terry stitches, which are made through a clockwise rotation of the cylinder, and non-terry stitches, which are made through a counterclockwise rotation, are combined to form terries on the wales. In a clockwise rotation, terry stitches always appear on the same wales. Similarly, terry stitches appear on the same wales in a counter-clockwise rotation. The product made by this method does not have a terry-pressure distribution or terry thickness that corresponds to the shape of the sole or to the distribution of the foot pressure when the foot touches the ground as the wearer walks.